Encased electrical time switch having externally operable setting means



Feb. 15, 1966 E. T. BUCKERIDGE ETAL 3, 3 ,8 ENCASED ELECTRICAL TIMESWITCH HAVING EXTERNALLY OPERABLE SETTING MEANS Filed Feb. 17, 1964United States Patent Ofiice smears ENQASED ELECTRIQAL TIME SWITCH HAVWGEXTERNALLY OPERABLE SETTING MEANS Edward Thomas Buclreridge and LeslieGeorge Mountjoy Payne, both of New Bridge Works, Bath, Somerset, EnglandFiled Feb. 17, 1964, Ser. No. 345,391 Claims priority, application GreatBritain, Mar. 15, 1963, 10,319/ 63 5 Claims. (Cl. 74-568) This inventionrelates to an externally operable setting means for encased electricaltime switches of the known kind in which there is a rotary dialgraduated in time intervals, around the periphery of which dial are anumber of switch-operating tappets which can be clamped fixedly inrelation to the dial in adjustable positions so as to actuate a switchinto ON and OFF positions as the dial is rotated by a timepiece such asa synchronous electric motor or a clockwork mechanism; such a kind oftime switch is, for the purpose of the present invention, of the typeenclosed within a casing having a transparent lid through which the dialmay be viewed. Such a kind and type is referred to herein as anelectrical time switch of the type described. in the followingdescription a tappet means a member adjustably movable over the face ofthe time dial, adapted to be clamped in a requisite position, andcarrying a pin or equivalent for engaging an electric switch operatingpart. The phrase consumer-operated tappet or consumer-tappet is used todescribe such a tappet which is adjustable from the exterior of theencased time switch, such as by a consumer of the current under thecontrol of the time switch.

Commercial Undertakings supplying electricity (in many countries and inmany areas in the United Kingdom) allow consumers to use the supply atcertain times of the day at a lower tariff than normally, these timesbeing usually referred to as OFF PEAK periods. To enable this practiceto be carried into effect, a time switch is usually mounted in a casinghaving a lid which can be closed and sealed so that an authorisedrepresentative of the Supply Undertaking, having set the ON and OFFtappets at time positions conforming with the limits of the OFF PEAKperiods, can then close and seal the lid with the consequence that noconsumption of electricity can take place outside said limits.

Normally, the foregoing arrangement means that the consumer, althoughprevented from using electricity outside the OFF PEAK limits, mustnecessarily have the supply switched on during the entire period betweenthe limits. This is not always desirable; for instance, to quote oneexample, when the supply is required merely to store heat for use duringa time outside the OFF PEAK period, then for reasons of economy theconsumer may require to delay the switching ON time so that the maximumstorage temperature will be reached at or shortly before the OFF PEAKlimit when the supply would be cut oh. by the time switch, and since theheating requirements may vary it then becomes desirable to be able tovary this time when the heaters will be switched ON. This is only oneexample of need for the consumer to be able to shorten the period ofconsumption between the fixed limits which have been pre-set by theSupply Undertaking. Although, usually, it would be the ON switchingoperation which would be varied, it is to be understood that the OFFswitching time-point may also be varied.

The object of the present invention is to enable the consumer to varythe ON or OFF time for the period .during which he is consuming electriccurrent, within the .pre-sct OFF PEAK period, without opening the casingas sealed by the authorised servant of the Supply Under- 3,234,814Patented Feb. 15, 1956 taking, and without liability of the OFF PEAKperiod being extended one way or the other, i.e. either past the fixedON or the fixed OFF limits.

In general, the invention comprises a tappet mechanism for fixing to thetransparent lid of a time switch casing, said mechanism having anoperating knob or equivalent exterior of the lid for mounting in aposition co-axial with the time dial of an enclosed switch, incombination with a tappet-holder and tappet for mounting on and rotationwith the time dial, and means controlled by said knob to turn the tappetabout the axis of said holder in relation to said time dial.

According to the said invention an electrical time switch of the typedescribed is provided with a tappet-holder mounted on the dial to rotatetherewith, said holder carrying a consumer-operated tappet adjustablyrotatable in relation to the holder and co-acting with the dial, incombination with a device fixed to the transparent lid to enable theconsumer tappet to be adjusted from the exterior of the casing, saiddevice comprising a spindle passed through a hole in the lid and havingan operating knob or equivalent mounted thereon outside the lid, and anarm or equivalent means mounted on and movable by the spindle inside thelid, said arm being disposed in con nectable relationship with gearingcarried by the tappetholder through which the consumers tappet can beadjusted on the latter to a required dial position, said tappetholdercomprising a first shaft for keyed attachment to the dial shaft, and thesaid gearing comprising a first gear wheel fixedly carried by said firstshaft, a second gear wheel rotatably mounted on said first shaft andfixedly carrying the consumer-tappet, the two gear wheels beingsuperimposed, of the same diameter, but with different teeth number, aplanet pinion carrier rotatable on said first shaft and provided with aplanet pinion engaging both gear wheels, said planet pinion carrierhaving a projection for engagement by the arm or equivalent mounted onthe spindle of the said operating knob.

The tappet mechanism just described may be employed as an attachment forthe purpose of adapting existing time switches to function according tothe invention instead of constructing it as part of an encased timeswitch.

An embodiment of the invention will be described by way of example withthe aid of the accompanying drawings wherein:

FIGURE 1 is a face view of part of a dial with a tappetholder andconsumer-tappet in position and is a section on the line Il of FIGURE 2;

FIGURE la is a fragmentary view of the time dial of FIGURE 1 on asmaller scale with the consumer tappet as the OFF tappet rather than theON tappet as shown in FIGURE 1;

FIGURE 2 is a side view partly in section.

Like numerals of reference represent the same or corresponding parts inthe two views.

In the embodiment an electric time switch of any suitable or knownconstruction (not shown) is enclosed in a casing having a hinged lidcapable of being sealed in the closed position and this is eitherentirely transparent or provided with a window, part of which is seen at1, through which the time dial 2 of the switch is visible. The time dialis usually provided with at least one pair of ON and OFF tappets, butpreferably two pairs so that two ON-OFF consumption periods within thefull 24- hour range of the dial may be catered for. For OFF PEAKoperation one consumption period is usually se lected for an eveningtime which could start at, say, 10 oclock pm. and terminate at 3 oclocka.m., and another perhaps for a short afternoon period. As usual thetappets are adjusted around the dial periphery so as to be clamped atpredetermined time graduations whence they are carried round by the dialto operate the switch. The t-appets have pins or equivalent for engagingthe switch mechanism and, for OFF FEAK periods with which the presentinvention is concerned, an authorized representative of the ElectricitySupply Undertaking sets the tappets so that the ON tap pets switch onthe supply at the commencement of the OFF PEAK. period, and the OFFtappets switch off at the conclusion. The lid is then closed and sealed.This is standard practice.

In the conventional construction of time switches there are two tappets,such as the tappets 5, each of which maybe clamped in a selectedposition to the time dial and each tappet contains means, such as a pin21, 21, for operating the switch, one tappet being the ON tappet and theother being the OFF tappet as illustrated in FIGURES l and 1a. Accordingto the particularly embodiment of the invention being described, the ONtappet is replaced by the stop 3 and the consumer-operated adjustabletappet 4 is included, having a pin 4a which not only serves to operatethe switch to the ON position but also eo-acts with the edge 22 of thetappet 5 and the edge 23 of the stop 3 to prevent the consumer tappet 4from being set to a position outside the time period defined by thetappet 5 and the stop 3. The OFF PEAK period selected for illustrationis a night-time period between pm. and 3 am. Thus the fixed stop 3 isadjusted to the 10 pm. position as seen in FIGURE 1. The consumer-tappet4 can be adjusted as will be described so as to enable the consumer todelay the switching ON of the current to some time later than that whichhas been pre-set by the stop 3. Alternatively the usual ON tappet may beleft effective for switching ON and the adjustable tappet of theinvention used as an OFF tappet in a position within the OFF PEAK zonebut preceding the preset OFF timing, in a case where the consumerdesires to commence consumption at the beginning of the OFF PEAK periodbut to out out earlier than at the end of such period. It will beappreciated that in this latter case the OFF tappet 5 will be replacedby a stop such as the stop 3'.

Centrally of the lid window 1, i.e. co-axially with the time dial 2,which is fixedly clamped on the spindle, indicated by dotted lines 19,of the time-piece, indicated by dotted lines 20, by means of the hollowshaft 2a in well known manner, there is mounted the first main part ofthe extra tappet mechanism of the invention. This is a manually operateddevice consisting of a knob 6 fixed to a spindle '7 which is passed fromthe exterior of the window 1 through a hole therein and is rotatably andslidably mounted in the hole, there being a compression spring 8encircling the spindle and housed in a hollow of the knob so as normallyto press the knob away from the window as shown in broken lines inFIGURE 2. The end of the spindle inside the casing has a radial arm 9extending from a mounting disc 11 frictionally clamped between annularflanges on the spindle which form a stop to limit the outward movementof the spindle '7 under the force of the aforesaid compression spring 8.By this construction and arrangement the knob may be pressed on to thelid window (full lines, FIGURE 2) so as to bring the radial arm 9 intoengagement with the planet arm or planet pinion carrier 17 of anadjustable tappetholder assembly indicated generally by the reference Adescribed in detail later and constituting a second main part of thetappet mechanism of the invention.

The adjustable tappet holder assembly A just mentioned is aself-contained element for fixing to the time dial 2 so as to rotatewith the said dial and carry around the extra tappet 4 provided by theassembly when it has been adjusted through the medium of the aforesaidknob 6. The said tappet holder A is in the form of a first shaft 11preferably longitudinally split at 13 at one end so as to frictionallyfit within a hollow frontal extension 2b of the time dial shaft 2a whichprotrudes through the middle of the time dial; The shaft 2a-2bfixcd-ly'carries the said dial. With a time-piece employing asquare-ended winding arbor for a reserve spring this arbor lies axiallywithin this dial shaft 20, 2b and the said shaft 11 of the tappet holderassembly A is also hollow so as to clear the winding arbor. A radialpin, feather of the like 12 on the tappet holder shaft 11 engages alongitudinal slot on the end of the dial shaft 2!) to provide a positivedriving connection from the dial shaft to the shaft 11.

The shaft 1 1 has mounted thereon first and second gear wheels 13 and 14which lie superimposed on one another, the first 13 being fixedlycarried by the shaft 11 and the second 14 being rotatable thereon. Thesegear wheels have the same diameter but differ in the number of teeth(say 42 on one against 44 on the other) but for all practical pun-posesthe pitch of each set of teeth may be regarded as similar. Also mountedon the shaft and rotatable with the second gear'wheel 14 to which it isfixed is the radially projecting consumer-tappet 4 which is suitablycranked to extend to the surface of the dial 2 to facilitatetime-setting and to overhang the periphery of the dai'l so that the pinor projection 4a thereon can actuate a switch member either ON or OFF aspreviously explained (in the embodiment ON).

Also carried rotatably on this tappet-holder shaft 11 is the aforesaidplanet pinion carrier 17 in the form of an arm extending radially, onwhich is rotatably mounted a planet pinion 15 meshing with both thehereinbefore described gear wheels 13 and 14. The fixed wheel 13 causesthe planet 15 to rotate on its own axis and roll around its toothedperiphery, as and when the carrier 17 is turned on the axis of thetappet-holder shaft 11, while the rotating planet imparts rotationalmovement to the rotatable gear wheel 14 thus carrying around theconsumer-tappet 4 for setting to a required time.

The gear train comprising sun gears 13 and 14 and planet pinion 15constitutes a well known type of high ratio differential gearing. Forexample, if the gear 14 has 44 teeth and the gear 13 has 42 teeth, thenif the planet pinion 15 is rotated for one complete revolution in aclockwise direction (when looking at the knob) by rotating the knob 6while pressed inwardly, then the pinion, in running around the gear 13,will be rotated through a total angle equivalent to 42 teeth and, sincethe gear 14 contains 44 teeth, it will be turned in the clockwisedirection by an angle equivalent to two of its teeth and the tappet 4will be rotated in the clockwise direction by i.e., part of arevolution. Due to the high ratio the drive is irreversible, that is tosay, the tappet 4 may be rotated by driving the knob 6 but rotationalpressure on the tappet 4 will not cause the planet gear 15 to be spunrapidly around to drive the knob 6, because the friction is too high.This is analagous to a high ratio worm gear in which the worm may bedriven by rotating the pinion but the pinion cannot be driven byrotating the worm because the gearing locks due to friction. Inconsequence, the gearing not only serves to adjust the tappet 4 butautomatically provides a lock so that the reaction pressure which isexerted upon it when it operates the switch does not cause anydisplacement of the tappet, and no special locking means need beprovided.

On the axis of the planet pinion a pin 16 extends fixedly from thecarrier 17 towards the first main part of the tappet mechanism i.e. theaforesaid operating device 6, 7, 8, 9. Thus when the knob 6 of thelatter is pushed in, the radial arm 9 on its spindle '7 is moved to aposition where the said planet carrier pin 16 is in its path, and bythis connectable relation between the arm and carrier rotation of theknob 6 brings about rotation of the planet carrier 17 and thus turns thetappet 4 to a time reading on the dial as required by the consumer.

In general, when using the auxiliary or consumertappet 4 the consumerpresses in the knob so as to engage the planet carrier 17 through pin16, and moves the carrier around the tappet-holder shaft 11, thusthrough the planet gearing 13, 14, 15 moving the tappet 4 to aselectedtime position between the OFF tappet 5 and the stop 3 which have alreadybeen pre-set to determine the limits of the OFF PEAK period. The pin laor consumer tappet 4 abuts the edge 22 of the tappet S and the edge 23of the stop 3 at the respective ends of its arcuate travel and, in thecase where the consumer tappet is the ON tappet, as shown in FIGURE 1,the pre-set ON stop 3 acts as the stop and not as a switching tappet.Accordingly the current, instead of being switched on by a tappet in theposition of the stop 3, will not be switched on until the time dial 2 isrotated to the point at which the consumer tappet 4 is enabled to closethe switch. In the example, as seen in FIGURE 1, the consumer haselected to switch on just before 12 oclock midnight.

When the tappet 4 contacts the switch mechanism pressure is transmittedback to the planet pinion 15. The gear ratio is such that any tendencyof the planet to turn and roll on gear 13 is prevented, the mechanismbecoming virtually locked by the gearing with the tappet remainingfirmly in position to operate the switch. On the other hand when themechanism is moved by the knob 6 there is free movement with very littlepressure to be overcome in order to turn the tappet 4. The degree offriction between the mounting of the radial arm 9 on the knob spindle 7is sufiicient to prevent Slip so as to do the work of adjusting theconsumer tappet 4 but insufficient to stop the time .piece it the tappetis brought hard up against the tappets (or tappet and stop) which havebeen pre-set according to the OFF PEAK period, in which case thefrictional mounting will slip.

We claim:

1. In an encased electric time switch including a time piece, a switchmember, a time dial, a fixed tappet for operating the switch member inone sense which may be set and locked at any desired position on thetime dial, a stop which may be set and locked at any other desiredposition on the time dial, the fixed tappet and stop defining a maximumtime period during which the switch member may be closed, an externallyoperable setting means comprising an adjustable tappet rotatable withrespect to said time dial to any desired position between said fixedtappet and stop for operating the switch member in the other sense,infinitely variable selflocking means protruding through the encasedtime switch for rotating said adjustable tappet, and coacting means onsaid stop and fixed tappet and said adjustable tappet which prevent saidadjustable tappet from being set to a position outside said time period,whereby the actual time period during which said switch is closed may bevaried within said maximum time period by the setting of said adjustabletappet.

2. In an encased electric time switch including a window, a time piece,a switch member, a time dial rotated flay the time piece inside saidcasing, a fixed tappet which may be set and locked at any desiredposition on the time dial to actuate the switch member to its ONposition, :a stop which may be set and locked at any desired position onsaid time dial, externally operable setting means comprising anadjustable tappet rotatable around said time dial between said fixedtappet and said stop for actuating said time switch to its OFF position,a spindle :axially and rotatably mounted through said window to 'theinterior of said casing, a knob outside said casing and mounted on theouter end of said spindle, a radial arm drivingly connected to the innerend of said spindle, a planet arm having a member engageable by saidradial arm inside said window; high ratio differential planet gearinginside said casing having one sun gear drivingly connected to saidadjustable: tappet, another co-axial sun gear drivingly connected tosaid time dial, and a pla et wheel mounted on said planet arm actuableby said knob 10 Niel? around said Sun gears in engagement with both ofthem, the two sun gears having slightly different numbers of teeth cuton the same pitch circle; said adjustable tappet being settable to anyposition between said fixed tappet and said stop by rotation of saidknob; said differential gearing forming a lock for the position of saidadjustable tappet except when said planet arm is actuated by said knob;whereby a predetermined maximum time period during which said switchmember may be in its ON position may be preset by said fixed tappet andsaid stop, and the time at which said switch member is actuated to itsOFF position is adjustable within the limits of said predetermined timeperiod by the setting of said adjustable tappet.

3. In an encased electric time switch according to claim 2 including aspring to urge said knob and spindle outwardly of said casing, saidmember on said planet arm being engageable by said radial arm when saidknob is pressed inwardly against the force of said spring, whereby saidknob is normally disengaged from said planet arm and is engageable forsetting said adjustable tappet by pressing said knob inwardly.

4. In an encased electric time switch including a window, a time piece,a switch member, a time dial rotated by the time piece inside saidcasing, 21 fixed tappet which may be set and locked at any desiredposition on the time dial to actuate the switch member to its OFFposition, a stop which may be set and locked at any desired position onsaid time dial, externally operable setting means comprising anadjustable tappet rotatable around said time dial between said fixedtappet and said stop for actuating said time switch to its ON position,a spindle axially and rotatably mounted through said window to theinterior of said casing, a knob outside said casing and mounted on theouter end of said spindle, a radial arm drivingly connected to the innerend of said spindle, a planet arm having a member engageable by saidradial arm inside said window; high ratio diiferential planet gearinginside said casing having one sun gear drivingly connected to saidadjustable tappet, another co-axial sun gear drivingly connected to saidtime dial, and a planet wheel mounted on said planet arm actuable bysaid knob to rotate around said sun gears in engagement with both ofthem, the two sun gears having slightly different numbers of teeth cuton the same pitch circle; said adjustable tappet being settable to anyposition between said fixed tappet and said stop by rotation of saidknob; said difierential gearing forming a lock for the position of saidadjustable tappet except when said planet arm is actuated by said knob;whereby a predetermined maximum time period during which said switchmember may be in its OFF position may be preset by said fixed tappet andsaid stop, and the time at which said switch member is actuated to itsON position is adjustable within the limits of said predetermined timeperiod by the setting of said adjustable tappet.

5. In an encased electric time switch according to claim 4, including aspring to urge said knob and spindle outwardly of said casing, saidmember on said planet arm being engageable by said radial arm when saidknob is pressed inwardly against the force of said spring, whereby saidknob is normally disengaged from said planet arm and is engageable forsetting said adjustable tappet by pressing said knob inwardly.

References Cited by the Examiner UNITED STATES PATENTS 37,110 12/1862Rochow 74--802 791,124 5/1905 Baehr 74-526 FOREIGN PATENTS 768,9615/1934 France.

BROUGHTON G. DURHAM, Primary Examiner.

MILTON KAUFMAN, Examiner.

1. IN N ENCASED ELECTRIC TIME SWITCH INCLUDING A TIME PIECE, A SWITCHMEMBER, A TIME DIAL, A FIXED TAPPET FOR OPERATING THE SWITCH MEMBER INONE SENSE WHICH MAY BE SET AND LOCKED AT ANY DESIRED POSITION ON THETIME DIAL, A STOP WHICH MAY BE SET AND LOCKED AT ANY OTHER DESIREDPOSITION ON THE TIME DIAL, THE FIXED TAPPET AND STOP DEFINING A MAXIMUMTIME PERIOD DURING WHICH THE SWITCH MEMBER MAY BE CLOSED, AN EXTERNALLYOPERABLE SETTING MEANS COMPRISING AN ADJUSTABLE TAPPET ROTATABLE WITHRESPECT TO SAID TIME DIAL TO ANY DESIRED POSITION BETWEEN SAID FIXEDTAPPET AND STOP FOR OPERATING THE SWITCH MEMBER IN THE OTHER SENSE,INFINITELY VARIABLE SELFLOCKING MEANS PROTRUDING THROUGH THE ENCASEDTIME SWITCH FOR ROTATING SAID ADJUSTABLE TAPPET, AND COACTING MEANS ONSAID STOP AND FIXED TAPPET AND SAID ADJUSTABLE TAPPET WHICH PREVENT SAIDADJUSTABLE TAPPET FROM BEING SET TO A POSITION OUTSIDE SAID TIME PERIOD,WHEREBY THE ACTUAL TIME PERIOD DURING WHICH SAID SWITCH IS CLOSED MAY BEVARIED WITHIN SAID MAXIMUM TIME PERIOD BY THE SETTING OF SAID ADJUSTABLETAPPET.